A short utility to use YAML configurations in Python and access their node data using the node1.node2.node3 format

YAMLNodeLoader.py

# 
# This program is a utility used by myself that I have released
# to the public under the GPLv3 license
#
# Copyright (c) 2021 IlluminatiFish.
# 
# This program is free software: you can redistribute it and/or modify  
# it under the terms of the GNU General Public License as published by  
# the Free Software Foundation, version 3.
#
# This program is distributed in the hope that it will be useful, but 
# WITHOUT ANY WARRANTY; without even the implied warranty of 
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License 
# along with this program. If not, see http://www.gnu.org/licenses/.
#


import yaml

import munch
import operator

class InvalidNodeException(Exception):
    pass

class ParserException(Exception):
    pass

def get_config_node(file, path):
    if not file.endswith('.yml') and not file.endswith('.yaml'):
        raise ParserException(f'Could not open {file} because is not a YAML file')

    config_file = open(file, 'r')

    try:
        config_file_dict = yaml.safe_load(config_file.read())
    except yaml.parser.ParserError:
        raise ParserException('Could not parse and load YAML configuration')

    # Pass the YAML loaded dictionary into the Munch module
    # So that is can return a class object so we can access
    # the YAML's config nodes (and the dictionaries' keys)
    munchified_config = munch.munchify(config_file_dict)

    # Use the operator module to convert a string YAML node
    # path into a python class attribute so that we can use
    # it with our munchified configuration and retrieve the
    # data from the node passed as @param path
    try:
        node_data = operator.attrgetter(path)(munchified_config)
    except AttributeError:
        raise InvalidNodeException('Invalid node path, the final node does not exist!')

    # We get a Munch object returned if the @param path is
    # not the full path to a valid node with data
    if isinstance(node_data, munch.Munch):
        raise InvalidNodeException('Invalid node path, please use a path that is the full node path to the data')

    if node_data is not None:
        return node_data
    else:
        raise InvalidNodeException(f'Invalid node data, there was no data found at your node path ({path})')